Cannot change hierarchy level even with a Premium account
1. Create initiative
2. Set it as 1st level of the hierarchy
AR - screenshot added
ER - to have possibilities to set "Initiative" as the first level of the hierarchy
Note: Premium plan activated (screenshot added)
you did already change the hierarchy level. The number in the first row is independent of the hierarchy, only the sequence is of importance.
Please make sure that the initiative is added as a parent of the epic (and - of course - the field "Parent Link" is added to the Epic's screens).